BRADFORD, Maine — Game wardens found a missing toddler who wandered out of the home while his parents slept Monday.

According to a release from Cpl. John MacDonald of the Maine Warden Service, the 18-month-old boy’s parents were sleeping after working overnight shifts Sunday night. When the father woke up at 1 p.m., the boy was missing.

The family believes the door may have been left open when the boy’s mother let the dog out around dawn, according to the warden service.

After searching around the house for the boy, the family called police.

Game wardens, state troopers with dogs and a Maine Forest Service helicopter responded shortly after 2 p.m. to the home on Isthmus Road in Bradford.

Game wardens and state troopers searched nearby buildings then followed dog tracks behind the home. At 4:20 p.m., Game Warden Jim Fahey found the missing boy about 0.6 mile behind the residence, sleeping in a tire rut on a grassy road.

Warden Fahey woke the boy, who appeared to be in good health, according to the release.

“We are thankful this incident had a good outcome as this could have been very tragic had the toddler not been located quickly,” according to a statement from the warden service.

Maine State Police are investigating the incident.